272 Proceedings of Indiana Academy of Science. 



ozone should be so low that the ordinary person does not notice its preseuco 

 on entering the room where it is used. Most of the cabinet, forms of 

 ozonizers have had perhaps ten times too great a capacity. 



There are certain places where it would be very desirable to have better 

 air. The crowded office and school room, the well attended movie theater 

 and church, or the basements of the large department stores, all have 

 trouble in secui-ing proper ventilation. There seem to be exhaled from the 

 human body certain substances which tend to make the air feel "close" 

 and after they have been breathed a little while a person becomes drowsy 

 and feels uncomfortable. To provide fresh air the atmosphere in a crowded 

 room has to be renewed sometimes as many as eight times in an hour. 

 In the cold weather this means that a lot of coal is required to warm up 

 all of this air which does not remain behind very long before it is dis- 

 carded. If some means could be provided for removing the deleterious 

 substances from this air allowing it to be recirculated there would be a 

 great saving in coal. The question then arises as to whether ozone will 

 accomplish this desirable result. About this question there has been waged 

 quite a little controversy pro and con. Emphatic statements have been made 

 on both sides so that it is somewhat difficult to decide just what the truth 

 of the matter is and a careful survey of the literature does not settle the 

 question either way, for there are not sufficient results of decisive experi- 

 ments to allow one to decide. Until the question has been cleared up by 

 high class experimental work, which will analyze the problem into its differ- 

 ent factors, we shall have to fall back upon certain positive results which 

 have been actually obtained in practice. 



In St. Louis, and the same thing must hold true here in Indianapolis, the 

 school rooms where colored children or the children of the "great unwashed" 

 portion of the population gather are rather hard to ventilate. In St. Louis 

 a number of the teachers in such schools were complaining of ill health and 

 great discomfort from the inadequate ventilation. The children too, would 

 become drowsy and the school work did not go forward as it should. When 

 some of the teachers threatened to resign the problem was put up to Mr. 

 Hallett, the chief engineer of the school board. He recommended the use of 

 ozone and had it installed in two of the worst schools. After that complaints 

 ceased and a questioniare sent out to the teachers found them enthusiastic 

 about the new system. Not only were they relieved from the almost 

 nauseating bad odors but the children were also taking an interest in their 

 work which they had not shown previously. The experiment has been so 

 successful that the use of ozone has been extended to many other school 

 buildings in that city and when a new building is put up an ozone system is 

 always included, • 



Economically, the big advantage of the system is that the air can be 

 recirculated so that a large part of the heat is saved. The writer visited 

 a school in the city of St. Louis where air was recirculated with the aid of 

 ozone. The odor of ozone was barely perceptible so that it was not at all 

 disagreeable. The children were not at all drowsy as they so often are in 

 the middle of the afternoon, but were very wide awake. The teachers on 

 being questioned, all were quite enthusiastic about the ventilation, and one 

 dear old frail lady said that she had not lost a day since the introduction 

 of ozone, whereas befoi'e she had lost a great deal of time. 



